Radiation supression

Abstract

An arrangement to mask direct view of the discharge end of a turbine through an exhaust duct extending downstream from the turbine. The turbine has an annular outlet. Two annular rows of fixed vanes are mounted in the outlet, one immediately upstream of the other. The two sets of vanes are reversely cambered so that the overall turning effect is insignificant and they are so located that each set of vanes blocks sight of the turbine through the gaps between the vanes of the other set.

I claim: 
     
       1. An arrangement for masking the outlet of a gas turbine, the turbine having an annular outlet and having a tailpipe extending from the outlet and terminating in a discharge port for the turbine exhaust, the said outlet including an outer wall and an inner wall; the masking arrangement comprising a first annular cascade of vanes extending between the walls adapted to swirl the turbine exhaust flow and a second annular cascade of vanes extending between the walls downstream of the first cascade adapted substantially to eliminate the swirl in the exhaust flow, the vanes of the two cascades being circumferentially staggered so as to mask the entire outlet from the discharge port. 
     
     
       2. A gas turbine engine comprising a gas turbine having an annular outlet for motive fluid defined by an outer wall and an inner wall, an exhaust duct extending from the outlet, and a discharge nozzle at the terminus of the exhaust duct, in combination with means for masking the turbine from the nozzle comprising a first annular cascade of vanes extending between the said walls adapted to swirl the turbine exhaust flow and a second annular cascade of vanes extending between the said walls downstream of the first cascade adapted substantially to eliminate the swirl in the exhaust flow, the vanes of the two cascades being circumferentially staggered so as to mask the entire outlet from the discharge port.